Planning rail hazmat shipments in the presence of random disruptions Manish Verma DeGroote School of Business, McMaster University, Canada, mverma@mcmaster.ca Armin Jabbarzadeh Department of Systems Engineering, ETS Montreal, Canada, armin.jabbarzadeh@etsmtl.ca Nader Azad Faculty of Business and Information Technology, UOIT, Canada, nader.azad@uoit.ca Railroad is one of the primary transportation modes for hazmat shipments in North America. However, the current academic literature has not studied the impact of disruption on rail hazmat shipments. This study proposes a bi-objective two-stage stochastic program that makes use a of new measure of risk to plan rail shipments in the presence of random disruptions. Key words : railroad transportation ; disruption management ; bi-objective stochastic optimization 1. Motivation Hazardous materials (hazmat), though harmful to humans and the environment, are integral to the industrial lifestyle and thus need to be transported in significant volumes. In North America, railroad is not only the primary mode for moving (non-bulk) hazmat shipments but also crucial to the economic growth of the entire continent, and hence the associated infrastructure is deemed critical (US DHS, 2018). Consequently, disruptions induced either by nature or man-made threats would have serious adverse impact. However, given the potential for spectacular events, most of the academic and industry initiatives have focused on the assessment and management of risk from hazmat shipments (Batta and Kwon, 2013). Thus, there is a need to study disruption to railroad operations, especially since such events are not infrequent (Kroon, Maroti and Nielsen, 2014; Azad, Hassini and Verma, 2016). It should be evident that the resulting risk management methods and optimization techniques should not only incorporate disruptions but also prescribe contingency plans for rail hazmat shipments. However, implementing such techniques is challenging because of two reasons: first, both the risk and the cost elements would tend to increase during disruptions since safe and economic routes might not be available; and second, it is difficult to evaluate the effectiveness of contingency plans because of the inherent trade-off between upfront cost to the railroad operator versus the possible mitigation (of risk and cost) resulting from the disruption. 1